//     Zepto.js
//     (c) 2010-2016 Thomas Fuchs
//     Zepto.js may be freely distributed under the MIT license.

;(function ($) {
  var touch = {},
    touchTimeout,
    tapTimeout,
    swipeTimeout,
    longTapTimeout,
    longTapDelay = 750,
    gesture,
    down,
    up,
    move,
    eventMap,
    initialized = false

  function swipeDirection(x1, x2, y1, y2) {
    return Math.abs(x1 - x2) >= Math.abs(y1 - y2)
      ? x1 - x2 > 0
        ? 'Left'
        : 'Right'
      : y1 - y2 > 0
      ? 'Up'
      : 'Down'
  }

  function longTap() {
    longTapTimeout = null
    if (touch.last) {
      touch.el.trigger('longTap')
      touch = {}
    }
  }

  function cancelLongTap() {
    if (longTapTimeout) clearTimeout(longTapTimeout)
    longTapTimeout = null
  }

  function cancelAll() {
    if (touchTimeout) clearTimeout(touchTimeout)
    if (tapTimeout) clearTimeout(tapTimeout)
    if (swipeTimeout) clearTimeout(swipeTimeout)
    if (longTapTimeout) clearTimeout(longTapTimeout)
    touchTimeout = tapTimeout = swipeTimeout = longTapTimeout = null
    touch = {}
  }

  function isPrimaryTouch(event) {
    return (
      (event.pointerType == 'touch' ||
        event.pointerType == event.MSPOINTER_TYPE_TOUCH) &&
      event.isPrimary
    )
  }

  function isPointerEventType(e, type) {
    return (
      e.type == 'pointer' + type || e.type.toLowerCase() == 'mspointer' + type
    )
  }

  // helper function for tests, so they check for different APIs
  function unregisterTouchEvents() {
    if (!initialized) return
    $(document)
      .off(eventMap.down, down)
      .off(eventMap.up, up)
      .off(eventMap.move, move)
      .off(eventMap.cancel, cancelAll)
    $(window).off('scroll', cancelAll)
    cancelAll()
    initialized = false
  }

  function setup(__eventMap) {
    var now,
      delta,
      deltaX = 0,
      deltaY = 0,
      firstTouch,
      _isPointerType

    unregisterTouchEvents()

    eventMap =
      __eventMap && 'down' in __eventMap
        ? __eventMap
        : 'ontouchstart' in document
        ? {
            down: 'touchstart',
            up: 'touchend',
            move: 'touchmove',
            cancel: 'touchcancel',
          }
        : 'onpointerdown' in document
        ? {
            down: 'pointerdown',
            up: 'pointerup',
            move: 'pointermove',
            cancel: 'pointercancel',
          }
        : 'onmspointerdown' in document
        ? {
            down: 'MSPointerDown',
            up: 'MSPointerUp',
            move: 'MSPointerMove',
            cancel: 'MSPointerCancel',
          }
        : false

    // No API availables for touch events
    if (!eventMap) return

    if ('MSGesture' in window) {
      gesture = new MSGesture()
      gesture.target = document.body

      $(document).bind('MSGestureEnd', function (e) {
        var swipeDirectionFromVelocity =
          e.velocityX > 1
            ? 'Right'
            : e.velocityX < -1
            ? 'Left'
            : e.velocityY > 1
            ? 'Down'
            : e.velocityY < -1
            ? 'Up'
            : null
        if (swipeDirectionFromVelocity) {
          touch.el.trigger('swipe')
          touch.el.trigger('swipe' + swipeDirectionFromVelocity)
        }
      })
    }

    down = function (e) {
      if (
        (_isPointerType = isPointerEventType(e, 'down')) &&
        !isPrimaryTouch(e)
      )
        return
      firstTouch = _isPointerType ? e : e.touches[0]
      if (e.touches && e.touches.length === 1 && touch.x2) {
        // Clear out touch movement data if we have it sticking around
        // This can occur if touchcancel doesn't fire due to preventDefault, etc.
        touch.x2 = undefined
        touch.y2 = undefined
      }
      now = Date.now()
      delta = now - (touch.last || now)
      touch.el = $(
        'tagName' in firstTouch.target
          ? firstTouch.target
          : firstTouch.target.parentNode
      )
      touchTimeout && clearTimeout(touchTimeout)
      touch.x1 = firstTouch.pageX
      touch.y1 = firstTouch.pageY
      if (delta > 0 && delta <= 250) touch.isDoubleTap = true
      touch.last = now
      longTapTimeout = setTimeout(longTap, longTapDelay)
      // adds the current touch contact for IE gesture recognition
      if (gesture && _isPointerType) gesture.addPointer(e.pointerId)
    }

    move = function (e) {
      if (
        (_isPointerType = isPointerEventType(e, 'move')) &&
        !isPrimaryTouch(e)
      )
        return
      firstTouch = _isPointerType ? e : e.touches[0]
      cancelLongTap()
      touch.x2 = firstTouch.pageX
      touch.y2 = firstTouch.pageY

      deltaX += Math.abs(touch.x1 - touch.x2)
      deltaY += Math.abs(touch.y1 - touch.y2)
    }

    up = function (e) {
      if ((_isPointerType = isPointerEventType(e, 'up')) && !isPrimaryTouch(e))
        return
      cancelLongTap()

      // swipe
      if (
        (touch.x2 && Math.abs(touch.x1 - touch.x2) > 30) ||
        (touch.y2 && Math.abs(touch.y1 - touch.y2) > 30)
      )
        swipeTimeout = setTimeout(function () {
          if (touch.el) {
            touch.el.trigger('swipe')
            touch.el.trigger(
              'swipe' + swipeDirection(touch.x1, touch.x2, touch.y1, touch.y2)
            )
          }
          touch = {}
        }, 0)
      // normal tap
      else if ('last' in touch)
        if (deltaX < 30 && deltaY < 30) {
          // don't fire tap when delta position changed by more than 30 pixels,
          // for instance when moving to a point and back to origin
          // delay by one tick so we can cancel the 'tap' event if 'scroll' fires
          // ('tap' fires before 'scroll')
          tapTimeout = setTimeout(function () {
            // trigger universal 'tap' with the option to cancelTouch()
            // (cancelTouch cancels processing of single vs double taps for faster 'tap' response)
            var event = $.Event('tap')
            event.cancelTouch = cancelAll
            // [by paper] fix -> "TypeError: 'undefined' is not an object (evaluating 'touch.el.trigger'), when double tap
            if (touch.el) touch.el.trigger(event)

            // trigger double tap immediately
            if (touch.isDoubleTap) {
              if (touch.el) touch.el.trigger('doubleTap')
              touch = {}
            }

            // trigger single tap after 250ms of inactivity
            else {
              touchTimeout = setTimeout(function () {
                touchTimeout = null
                if (touch.el) touch.el.trigger('singleTap')
                touch = {}
              }, 250)
            }
          }, 0)
        } else {
          touch = {}
        }
      deltaX = deltaY = 0
    }

    $(document)
      .on(eventMap.up, up)
      .on(eventMap.down, down)
      .on(eventMap.move, move)

    // when the browser window loses focus,
    // for example when a modal dialog is shown,
    // cancel all ongoing events
    $(document).on(eventMap.cancel, cancelAll)

    // scrolling the window indicates intention of the user
    // to scroll, not tap or swipe, so cancel all ongoing events
    $(window).on('scroll', cancelAll)

    initialized = true
  }

  ;[
    'swipe',
    'swipeLeft',
    'swipeRight',
    'swipeUp',
    'swipeDown',
    'doubleTap',
    'tap',
    'singleTap',
    'longTap',
  ].forEach(function (eventName) {
    $.fn[eventName] = function (callback) {
      return this.on(eventName, callback)
    }
  })

  $.touch = { setup: setup }

  $(document).ready(setup)
})(Zepto)
